<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title></title>
		<style>
			#div_con{
				width: 300px;
				border: 1px solid #A52A2A;
			}
			#div01{
				width: 100px;
				height: 100px;
				background-color: aquamarine;
				float: left;
			}
			#div02{
				width: 150px;
				height: 150px;
				background-color:brown;
				float: left;
			}
			#div03{
				width: 200px;
				height: 200px;
				background-color: pink;
				float: left;
			 
			}
			#div04{
				width: 100px;
				height: 200px;
				background-color: red;
				clear: both;
			}
		</style>
	</head>
	<body>
		<div id="div_con">
		<div id="div01">这是第一个div</div>
		<div id="div02">这是第一个div</div>
		<div id="div03">这是第一个div</div>
		<div id="div04">aaaa</div>
		</div>
	</body>
</html>
